Delta type robots are known for use in association with many industrial applications to automate certain functions that have been previously carried out manually. In particular these delta robots have been suspended over a conveyor type system to grasp and move small objects rapidly and with a high rate of precision. The linkages of the delta robot hang downwardly and move a mounting plate and support a tool or other device to carry out a particular function or task.
Examples of such industrial robots are shown in U.S. Pat. No. 6,766,711 and US Published Application 2006/00182602.
These designs include an upper mounting base plate having three arm linkages pivotally secured thereto and each arm linkage includes first and second arms pivotally secured to each other. These arm linkages allow precision controlled movement of the mounting plate by means of motors provided at the base plate.
There have also been a number of variations of the delta type robot, for example, a counter balanced arrangement is shown in International Application WO 2010/128849. A further design that allows rotation of the mounting plate is shown in US Publication 2008/00262653.
The above identified delta robotic designs all include a base plate where the lower arm of each arm linkage is only pivotally secured to the base and the upper arm is a parallelogram type linkage that is pivotally secured in a manner to provide a further degree of movement to the lower arm. With this arrangement, the upper arm can pivot relative to the lower arm and it can also pivot in a second direction due to the parallelogram type linkage. With the known delta type robots in a neutral position of the arm linkages, each lower arm extends outwardly away from the base such that the pivot point with the upper arm is exterior to the base and exterior to the pivot position of the related lower arm on the base.
The present invention departs from this accepted configuration and uses a modified arm linkage arrangement for a delta robot. In a preferred embodiment, this modified arm linkage is advantageously used on a mobile base. This structure, when used on a mobile base, has a number of advantages with respect to reaching over surfaces such as a table edge and enhancing stability. The combined mobile base and linkage also preferably includes both an anticipatory and a responsive action to undesirable forces that may be suddenly applied to the robot to reduce the effect thereof.